static CharEscaper createSimpleCharEscaper(ImmutableMap<Character, char[]> replacementMap) {
    return new CharEscaper() {
      @Override
      protected char[] escape(char c) {
        return replacementMap.get(c);
      }
    };
  }

  // A trivial non-optimized escaper for testing.
  static UnicodeEscaper createSimpleUnicodeEscaper(ImmutableMap<Integer, char[]> replacementMap) {
    return new UnicodeEscaper() {

          // TODO(lukes): in a real implementation we would need to handle overflow conditions
          int maxChars = (int) (size.get().intValue() * cs.newDecoder().maxCharsPerByte());
          char[] buffer = new char[maxChars];
          int bufIndex = 0;
          int remaining = buffer.length;
          try (InputStreamReader reader = new InputStreamReader(byteSource.openStream(), cs)) {
            int nRead = 0;

  }

  public void testCharsIgnored() {
    for (char c : IGNORED.toCharArray()) {
      String str = String.valueOf(c);
      assertEquals(str, c, Ascii.toLowerCase(c));
      assertEquals(str, c, Ascii.toUpperCase(c));
      assertFalse(str, Ascii.isLowerCase(c));
      assertFalse(str, Ascii.isUpperCase(c));
    }
  }

  public void testCharsLower() {
    for (char c : LOWER.toCharArray()) {
      String str = String.valueOf(c);

    assertPutString(new char[] {'p', HashTestUtils.randomLowSurrogate(new Random())});
  }

  public void testPutStringWithHighSurrogate() {
    // we pad because the dummy hash function we use to test this, merely copies the input into
    // the output, so the input must be at least 32 bits, since the output has to be that long
    assertPutString(new char[] {'p', HashTestUtils.randomHighSurrogate(new Random())});
  }

            + "abcdefghijklmnopqrstuvwxyz"
            + "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
            + "1234567890";
    assertEquals(s, xmlEscaper.escape(s));

    // Test ASCII control characters.
    for (char ch = 0; ch < 0x20; ch++) {
      if (ch == '\t' || ch == '\n' || ch == '\r') {
        // Only these whitespace chars are permitted in XML,
        if (shouldEscapeWhitespaceChars) {

}

// Exercises tensorflow's C API.
int main(int argc, char** argv) {
  TF_InitMain(argv[0], &argc, &argv);

  struct TF_StringStream* s = TF_GetLocalTempDirectories();
  const char* path;

  if (!TF_StringStreamNext(s, &path)) {
    fprintf(stderr, "TF_GetLocalTempDirectories returned no results\n");
    return 1;
  }

  char file_name[100];
  time_t t = time(NULL);

   * false} for {@code boolean} and {@code '\0'} for {@code char}. For non-primitive types and
   * {@code void}, {@code null} is returned.
   */
  @SuppressWarnings("unchecked")
  public static <T> @Nullable T defaultValue(Class<T> type) {
    checkNotNull(type);
    if (type.isPrimitive()) {
      if (type == boolean.class) {
        return (T) Boolean.FALSE;
      } else if (type == char.class) {
        return (T) Character.valueOf('\0');

import java.io.FilterWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
import org.jspecify.annotations.NullUnmarked;

/**
 * A char sink for testing that has configurable behavior.
 *
 * @author Colin Decker
 */
@NullUnmarked
public class TestCharSink extends CharSink implements TestStreamSupplier {

  private final TestByteSink byteSink;

  }

  /**
   * Reads a char as specified by {@link DataInputStream#readChar()}, except using little-endian
   * byte order.
   *
   * @return the next two bytes of the input stream, interpreted as a {@code char} in little-endian
   *     byte order
   * @throws IOException if an I/O error occurs
   */
  @CanIgnoreReturnValue // to skip some bytes
  @Override
  public char readChar() throws IOException {

    val c = name[i]
    require(c in '\u0021'..'\u007e') {
      "Unexpected char 0x${c.charCode()} at $i in header name: $name"
    }
  }
}

internal fun headersCheckValue(
  value: String,
  name: String,
) {
  for (i in value.indices) {
    val c = value[i]
    require(c == '\t' || c in '\u0020'..'\u007e') {
      "Unexpected char 0x${c.charCode()} at $i in $name value" +